It has been a while since we last talked about 2.5-inch hard disk drives. It is time to introduce to you new models with storage capacities exceeding half a terabyte already. Moreover, we are also going to present to you our new testing methodology.

Seagate Momentus 5400.6: ST9500325AS – 500 GB

As we are going to pit new HDDs against their predecessors, it would be wrong not to include the Seagate Momentus 5400.6 into the comparison.

Seagate Momentus 5400: ST9640320AS – 640 GB

As you might expect from a company aspiring to be the leader of the industry, Seagate has already introduced its 640GB model. The new series is called simply Momentus 5400 without any ordinal number. Does it mean we are up to a new series of 5400RPM drives in the nearest future?

One new series has already come out without much fuss, yet the Momentus Thin is nothing exceptional. It seems to be a single-platter model in a 7mm case and its small dimensions should be appreciated by netbook and tablet PC makers.

Seagate Momentus 7200.4: ST9500420AS – 500 GB

The last member of the Seagate team is the Momentus 7200.4, the first 500GB drive to have a spindle rotation speed of 7200 RPM. It also has a double amount of cache (16 megabytes) compared with its cousins that have slower platters. The Seagate website announces a 750GB model already which seems to hail from a whole new series that, like the junior one, lacks an ordinal number in the end of the name. Unfortunately, we haven’t yet got these drives for tests.

The Seagate Momentus XT is yet another highly anticipated product but we will cover it in our next review.